burroughs B 9489 User manual

B9489
FLEXIBLE DISK DRIVE
TECHNICAL
MANUAL
Burroughs m
FIELD ENGINEERING
FIELD ENGINEERING PROPRIETARY DATA.
The information contained in this document is proprietary to Burroughs Corporation. The information
or this document is not to be reproduced. shown, or disclosed outside Burroughs Corporation without
written permission
of the Patent Division.
This material
is furnished for Burroughs Field Engineering Personnel. and is not furnished to customers
except
under special License Agreement.. .
THIS DOCUMENT IS THE PROPERTY OF AND SHALL BE RETURNED TO BURROUGHS
CORPORATION. BURROUGHS PLACE, DETROIT~ MICHIGAN 48232.
F.E. Dist. Code~
Printed In U.s. America December
1979 (\
1
2
3
INTRODUCTION
AND
OPERATION
FUNCTIONAL
DETAIL
.CIRCUIT
4 ADJUSTMENTS
5
6
7
8
9
10
A
B
c
MAINTENANCE
PROCEDURES
INSTALLATION
PROCEDURES
For Library Binder 424
Form 2102141-001

ii
Burroughs believes that the information described in this
manual
is accurate and reliable, and much care has been
taken inits preparation. However, no responsibility, financial
or otherwise,
is accepted for any consequences arising out of
the use of this material. The information contained herein is
subject to change. Revisions may be issued to advise of such
changes and/or additions.
Correspondence regarding this document should be addressed directly
to TechnicalDocumentationDepartment, Technical Information Organ-
ization, Burroughs Machines limited, Cumbernauld, Glasgow, Scotland,
G680LN.

Bu.rronghs
PUBLICATION
CHANGE
NOTICE
2102141-002
peN No.: ___________ ---------
Date: __
J
_an_ua_ry_l_9_80 _____ _
Publication Title: B 9489 Flexible Disk Drive Technical Manual
Other Affected Publications:~N_on_e _____ ~~_~ ________________ ~
Super~des: ____ N_o_n_e ____________________________________________________________________ _
Description
This Publication Change Notice proVides additional information regarding the Preventive Maintenance Guide.
Remove the following pages :
iii & iv
5-1 & 5-2
Add the following pages :
iii & iv
5-1 & 5-2
Retain this PCN as a record of changes made to the basic publication.
FIELD ENGINEERING PROPRIETARY DATA
The information contained in this document is proprietary to Burroughs Corporation. The information or
this document is not to be reproduced, shown, or disclosed outside Burroughs Corporation without written
permission of the Patent Division.
This material
is furnished for Burroughs Field Engineering Personnel, and is not furnished to customers
except under special License Agreement.
THIS DOCUMENT IS THE PROPERTY OF AND SHALL BE RETURNED TO
BURROUGHS CORPORATION, BURROUGHS PLACE, DETROIT, MICHIGAN 48232.
F.E. DiSI., SO
Code 1.... _____ _
Printed in U.S. America
iii
For Library Binder424
Form 2102141

Bu.rrou.ghs
2102141-001peN No.: __________________ _
PUBLICATION
CHANGE
NOTICE
Date: __ De_c_e_m_b_er_19_7......;9 _____ _
Publication Title: _..4:B!:...I9~4.:.:;8~9....!iFll..t.e:...!X1.!:t.·b~1~e...t:::D~isk~Dt;::;,jnu.·vue~t~e~c!.!:ihnwi~cal~Mwan~u_alk...._ ________________ _
Super~des: ___N __ o_ne ____________________________________________________________________ __
Description
this Publication Change Notice provides Section 4, Adjustments
Remove the following:
Title
A
Page
vthru vi
4-1 thru 4-2
Insert the following:
Title
ii
iii thru viii
4-1 thru 4-10
Retain this PCN as a record of changes made to the basic publication.
FIELD ENGINEERING PROPRIETARY DATA
The information contained in this document is proprietary to Burroughs Corporation. The information or
this document is not to be reproduced, shown, or disclosed outside Burroughs Corporation without written
permission of the Patent Division.
This material
is furnished for Burroughs Field Engineering Personnel, and is not furnished to customer.
except under special License Agreement.
THIS DOCUMENT IS THE PROPERTY OF AND SHALL BE RETURNED TO
BURROUGHS CORPORATION, BURROUGHS PLACE, DETROIT, MICHIGAN 48232.
F.E. DiSI., BD
C()de~. _____ ..I
Printed in U.S. America
iii
For Library Binder 424
Form 2102141-001

Burroughs - B 9489 Flexible Disk Drive Teclmical Manual
LIST OF EFFECTIVE PAGES
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LIST OF EFFECTIVE PAGES
Page
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2-1 thru 2-25
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4-1 thru 4-10
5-1 thru 5-4
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Burroughs -B9489 Flexible Disk Drive Technical Mariual
Section 1
INTRODUCTION AND OPERATION
General Description. •
Configurations.
Applications .
Major Assemblies.
Motor and Spindle
Receiver. . • . .
Stepper Motor and Leadscrew. . .
Carriage. . .
Pressure Pads . .
Magnetic Heads
Recording Mode .
Printed Circuit Board
Operation . . . . .
Flexible Disk (Mini-Disk)
Sector Configuration. .
Data Configuration
Recording Mode . . . . . .
Functions
Seek
..
Write. . .
Read
..
Physical and Electrical Characteristics •
Physical. . . . . .
Electrical . . . . .
Recording Characteristics
Format. .
Data Access.
Flexible Disk .
Jacket . . .
Disk Handling. . .
Operating Procedures . . . .
Indicators and
Control. .
Electrical Interconnections, Host
to
Master Interface. . . . . . .
Master
DC Supplies. . . . ...
Master Drive to Slave Drive Interface
Line Power and Grounding. . . . .
Section 2
.FUNCTIONAL DETAIL
Positioner . . . . . • •
General Description. . . • .
Mechanics
,; • . . . • . .
Carriage. .. ..•.
Magnetic Heads . • .
Electronics.. .•••
File OP. . .
Address Latches .
Address 00 Detector. .
Illegal Address. . . • . .
Current Address Counter and Comparator
2102141-001
TABLE OF CONTENTS
Page
1 .... 1
1-2
1-2
1-3
1-3
1-3
1-3
1-4
1-4
1-4
1-4
1-5
1-5
1-5
1-5
1-6
1-6
1-7
1-7
1-7
1-7
1-7
1-7
1-7
1-7
1-7
1-7
1-8
1-8
1-8
1-9
1-9
1-9
1-10
1-10
1-10
2-1
2-1
2-1
2-2
2-2
2-2
2~3
2-4
2':"'"4
2-4
2-4
Section 2 (Continued)
. Stepper Motor Drivers .
Stepper Motor Register.
Stepper Motor. ••.• • •
Positioner Clock. .
Clock
Control. .
Direction Control. .
Position Settled .
Head Select. . . . .
Head Load Solenoids and Tiler .
Index and Sector Pulses. .
Write. . . . .
General. . . .
Write Clock. . • . .
Write Data Encode .
Unit Selection. . .
Write Inhibit • . .
Write and Erase Drivers. .
Read Head Select. . . . . •
Read Channel. . . • • •
Digital Fi Iter. • . . • •
Data Decode .
General. . •
Selection . . .
Standardizer and PLL •
PLL
.....•
Read Enable Delay .
Read Clock.
Data Window
Section 3
CIRCUIT DETAIL
General. . .
Section 4
ADJUSTMENTS
Introduction . .
Special Tools . .
Align me nt Pisk . . • .
B80 Hex Keyboard Collated Table • •
Alignment Track Selection using B80 MTR
Alignment Meter Operating Instructions
Adjustments • . • • • . • . •
Backlash Nut Adjustment.. . • . .
Track
to Track Alignment Check
Track to Track Alignment Adjustment.
Circumferential Alignment . . . •
Track 00 Adjustment • . • • • .
Phase Locked Loop and Data Windows.
DTM
·1000 or BDM 1250
DTM 1000 . . .
BDM 1250. . . . . . . . . .
Section 5
MAINTENANCE PROCEDURES
Removal and Replacement Procedures. .
Page
2-6
2-6
2-8
2-8
2-9
2-9
2-9
2-11
2-11
2-11
2-15
2-15
2-16
2-16
2-18
2-18
2-18
2-18
2-18
2-21
2-21
2-21
2-21
2-23
2-23
2-23
2-25
2-25
3-1
4-1
4-1
4-1
4-1
4-1
4-2
4-2
4-2
4-3
4-3
4-5
4-7
4-7
4-8
4-9
4-9
5-1
v

Burroughs -B9489 Flexible Disk Drive Technical Manual
TABLE OF CONTENTS (Continued)
Section 5 (Continued)
Fascia . . .
Receiver. . . . • . .
Stepper Motor and Carriage .
Head Solenoids
I..arnps . . . . . . . . . . .
Pressure Pads . .
..'
Drive Belt . .
Page
5-1
5-1
5-1
5-2
5-2
5-2
5-2
Section 5 (Continued)
Preventive Maintenance Fuide. . . . .
Fault
Finding. . . . . .
Recovery
of Conta~inated Disks.
Certified Disks. . . . . . . . . .
Section 6
INSTALLATION PROCEDURES
Installation Procedures. . .
LIST OF ILLUSTRATIONS
Figure
Page
Figure
I-I
Complete Unit.
1-1
2-16
Read Block Diagram.
1-2
Master/Slave Configuration.
1-2
2-17 Read Channel Test Points .
1-3
Major Assemblies.
1-2
2-18
Schematic -Read Channel
1-4
Stepper Motor and Leadscrew.
1-3
2-19
PLL/Data Relationship.
1-5
Carriage Assembly
1-4
2-20 Data Decode Timing.
1-6
Diagrammatic Recording Head
1-4
2-21
Schematic -Read Data Decode .
1-7
Magnetic Head Layout .
1-5
2-22 Worst Case Peak Shift
1-8
Head Schematic
1-5
1-9
Track Format (Upper Side)
1-5
3-1 Logic Example
1-10
Track Format (Lower Side)
1-5
3-2 SN7400 QJ.lad 2-Input NAND Gate .
1-11
Sector Configuration
1-6
3-3
SN7402 Quad 2-Input NOR Gate
1-12
Encoding Comparison
1-6
3-4
SN7404 HEX Inverter
~
1-13 Disk.
1-8
3-5 SN7405 HEX Inverter with Open
1-14 Jacket
1-8
Collector Output
.'
1-15
Operator Controls
1-9
3-6
SN7410 Triple 3-Input NAND Gate.
1-16
Common Electronics
1-11
3-7 SN7420 Dual 4-Input NAND Gate .
1-17 Block Diagram. 1-12
3-8
SN7426 Quad 2-Input High Input
Voltage Interface NAND Gate with Open
2-1
Positioner Mechanics (Top View)
2-1
Collector Output
2-2 . Carriage (Side View) .
2-2
3-9
SN7438 Quad 2-Input Interface NAND
2-3
Positioner Electronics Block Diagram .
2-3
Gate with Open Collector Output .
2-4
Schematic -Address Counter/
3-10
SN74132 Quad 2-Input NAND Gate
Comparator
2-5
-Schmitt Triggers
2-5
Schematic -Positioner Clock and
3-11
SN7427 Triple 3-Input NOR Gate
Stepper Motor Drivers.
2-7
3-12
SN75452 Dual NAND Driver .
2-6
Stepper Motor. ,
2-8
3-13
SN7474 Dual D-type Flip Flop
2-7
Positioner Clock Start-Up .
2-8
3-14 ITT96015D Retriggerable Monostable
2-8
Schematic - Head Load Control.
2-12
Multivibrator.
2-9
Schematic -Index/Sector J:lulses.
2-13
3-15 9602 Dual Retriggerable, Resettable,
2-10
Index and Sector Generation.
2-14
Monostable Multivibrator.
2-11
Write Block Diagram.
2-15
3-16
8284 Hexadecimal Up/Down Counter.
2-12 Write Timing
2-16
3-17 9308 Dual 4-Bit Latch .
2-13 Schematic -Write Data Encoder.
2-17
3-18 9322 Quad 2-Input Multiplexor .
2-14
Schematic -External Interface Logic. 2-19
3-19 9324 5-Bit Comparator.
2-15
Schematic -Write Driver .
2-20
3-20 733 Differential Amplifier.
vi
page
5-2
5-2
5-2
5-2
6-1
Page
2-21
2-21
2-22
2-23
2-23
2-24
2-25
3-1
3-2
3-~
3-2
3-3
3-3
.3-3
3-3
3-4
3-4
3-4
3-4
3-5
3-5
3-5
3-6
3-6
3-6
3-6
3-7

I
Figure
3-21
3-22
3-23
3-24
3-25
3-26
3-27
4--1
4--2
Burroughs - B 9489 Flexible Disk Drive Technical Manual
LIST OF ILLUSTRATIONS (Continued)
Page Figure
710 High Speed Differential Comparator
3-7
4--3 Oscilloscope Wave Form
7496 5-Bit Shift Register
3-7
4--4 Component Layout Showing the Posi-
NE 562B Phase Locked Loop.
3-8
tion of Recommended Test Point
TIL 31 or 1A48B Photo Emissive Diode
3-9
4--5 Correct Waveform
TIL
81 or 2B50B Silicon Photo Transistor
3-9
4--6 Incorrect Waveforms
Delay Une 300ns.
3-9
4--7 Unstable Waveforms
High Power Transistor 2N6055 or 4--8 Data Window Adjustment .
TIP640.
3-9
5-1 Stepper Motor and Carriage Assembly .
Backlash Nut
Adjustment.
4--2
5-2
50/60Hz Conversion.
Locking Plate Clearance 4--3
5-3
Connection Block Diagram.
LIST OF TABLES
Page
Table
1-1 Logic Interface Between Host System
1-2
2-1
3-1
4--1
4--2
5-1
and Master Drive . . . . .
DC Supplies to the Master Drive. .
Stepper Truth
Table. .
Index
of Modules.
PCB Test Points
1-9
1-10
2-6
3-1
4--1
4-2
5-3
2102141-001
Page
4--6
4--6
4--8
4--8
4--8
4--9
5-1
5-·2
5-4
I
vii